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Selection and characterization of bispecific ADAPT molecules for enhanced biodistribution in cancer therapyBorin, Jesper January 2020 (has links)
Established biopharmaceuticals such as antibodies and derivatives thereof are relatively large. In cancer therapy, this creates a steep drug concentration gradient within tumors, leaving cells far from blood vessels effectively untreated. Continuous pseudo treatments should foster the development of drug resistance and might lead to eventual disease relapse. Drug concentration gradients can be operationalized as tissue penetration efficiencies, which are functions of molecular size. However, small particles are also subject to potent renal clearance, collapsing the therapeutic window beyond clinical applications. In this master’s thesis, spatial bispecificity was engineered into a single albumin binding domain (ABD). Resulting ABD derived affinity proteins (ADAPTs) are saved from urinary excretion by the grace of HSA, but in the more static microenvironment of tumors, following HSA dissociation, they are capable of tissue penetration efficiencies bestowed only upon smaller particles. To this end, phage display was used to raise ADAPTs against the cancer associated proteins human epidermal growth factor receptor 2 (HER2) and carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6), but also the inflammation marker C-reactive protein (CRP). Via Sanger sequencing, 9 variants were picked for protein production and characterization, among which two spatially bispecific binders were found. ADAPTs were also evaluated for aggregation tendencies, structural conformity to library design, and thermal stability. One ADAPT, binding HER2, passed all tests of initial characterizations. Deep sequencing was used to analyze selection output, from which many more binders should be screened in future experiments. / Etablerade bioläkemedel liksom antikroppar och deras derivat är relativt stora protein. Som cancerterapeutiska skapar de således branta koncentrationsgradienter utgående från tumörpenetrerande blodkärl. Detta riskerar att lämna vissa cancerceller utanför det terapeutiska fönstret. Det svaga selektionstryck som således verkar i tumörperiferin fostrar cancerceller till att utveckla resistens mot detsamma. Koncentrationsgradienten beror på proteinets vävnadspenetrarande förmåga, vilken är en funktion av proteinets storlek. Mindre proteiner borde därmed lättare ackumuleras i hela tumören och förebygga resistensutveckling. Problemet med små proteiner är deras mycket korta halveringstid i serum, en följd av relativt obehindrad filtrering ut i urinen via njurarna. I det här examensarbetet utvecklades rumsbispecifika bindare av cancerassocierade protein med hjälp av fagdisplayselektioner från ett proteinbibliotek baserat på en enda albuminbindande domän (ABD). Resulterande ABD deriverade affinitetsprotein (ADAPT) undkommer ovan nämnda filtrering tack vare sin naturligt starka interaktion med humant serumalbumin (HSA). I den mer långsamt flödande tumörmikromiljön tillåts ADAPTerna efter albumindissociation sedan utöva en bland bioläkemedel överlägsen vävnadspenetration. Tre parallella selektionsspår utfördes mot de cancerassocierade målproteinerna human epidermal growth factor receptor 2 (HER2) och carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) samt den utsöndrade inflammationsmarkören C-reaktivt protein (CRP). Via Sangersekvensering kunde flera kandidater identifieras. Bland 6 karakteriserade ADAPTer uppvisade samtliga hög HSA-affinitet, tre konstaterades interagera specifikt med sitt målprotein, och två verkade binda även rumsbispecifikt. ADAPTer utvärderades även för sin benägenhet att bilda aggregat, strukturell överensstämmelse med experimentell design, och värmestabilitet. Endast en bindare, mot HER2, klarade sig genom alla prövningar som proteinkarakteriseringen innebar utan underkänt. Även en högparallel sekvensering utav selektionsresultat utfördes, men utanför de tidsramar som tillät ytterligare karakterisering.
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Essays on exchange rate models under a Taylor rule type monetary policyKim, Hyeongwoo 07 August 2006 (has links)
No description available.
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An analysis of antidepressant noncompliance in the private health sector of South Africa / Francois Naude SlabbertSlabbert, Francois Naude January 2014 (has links)
The main aim of the thesis was to measure antidepressant (AD) non-compliance, to determine which factors are closely associated with AD non-compliance and the consequences of prolonged AD non-compliance in the private health sector of South Africa. The empirical study followed an observational, prospective, cohort study using longitudinal medicine claims data provided by a nationally representative Pharmaceutical Benefit Management company (PBM) from 1 January 2006 to 31 December 2011.
Failure to respond to AD treatment and achieving remission has severe neurobiological and clinical consequences. The clinical consequences include increased social and functional impairment, higher risk for recurrence and relapse of a depressive episode, a weak treatment outcome, significant increase in treatment cost, over-utilization of health care systems, and ultimately an increased suicide risk. However, the neurobiological consequences are much more far reaching. One of the more serious yet under-recognized neurobiological complications of AD non-compliance is the development of antidepressant discontinuation syndrome (ADS), which is the result of non-compliance or the abrupt discontinuation of AD treatment. Altered serotonergic dysfunction appears central to ADS so that how an antidepressant targets serotonin will determine its relative risk for inducing ADS and thereby affect later treatment outcome. Low ADS risk with agomelatine versus other antidepressants can be ascribed to its unique pharmacokinetic characteristics as well as its distinctive actions on serotonin, including melatonergic, monoaminergic and glutamatergic-nitrergic systems.
After the first four months only 34% (n=12 397) of patients were compliant. What’s more a statistically significant association was found between active ingredient consumed and compliance (p < 0.0001). Only 26.2% of patients who received amitriptyline-containing products were complaint compared to 38.8% and 38.7% in the cases of venlafaxine and duloxetine, respectively. The current study found that females have a significantly higher prevalence of MDD and HIV/AIDS when compared to males.
The co-morbidity between HIV/AIDS and major depressive disorder (MDD) had a significant effect on AD treatment compliance as patients diagnosed with both HIV/AIDS and MDD (74.43. ± 32.03, 95%Cl: 71.51-77.34) displayed a lower compliance vs. MDD patients (80.94% ± 29.44, 95%Cl: 80.56-81.33). Noteworthy, observations were that 75% (p < 0.0217; Cramer’s V = 0.0388) of venlafaxine and 28.6% (p < 0.0197; Cramer’s V = -0.0705) of the paroxetine items were compliant in patients diagnosed with both HIV/AIDS and MDD.
The overall compliance (35.19% acceptable compliance; n = 42 869) of patients taking both ADs and GDs was weak. In the group receiving both AD and GDs, an increased AD treatment period was associated with a significant increase (p < 0.0001) in AD compliance (406.60 days; 95%Cl: 403.20 – 409.90 vs. 252.70 days; 95%Cl: 250.20 – 255.20). In this cohort amitriptyline (29.57%), mirtazapine (31.36%) and fluoxetine (32.29%) were associated with the lowest levels of compliance, while duloxetine (40.67%) was found to have the highest compliance. Lastly, ADs with highest non-compliance were associated with an increase use in GDs. Alprazolam (n = 10 201) and zolpidem (n = 9 312) were the most frequently dispensed GDs in combination with AD treatment.
In conclusion the current study confirms that AD non-compliance is as big an obstacle in developing countries as it is in developed countries. Antidepressant treatment non-compliance has far reaching
consequences especially with the development of ADS which further complicates MDD and might be a precursor for the development of TRD. Several factors were found to be closely associated with AD treatment non-compliance which include; pharmacological class of AD, gender, chronic co-morbid illnesses and a short treatment period. / PhD (Pharmacy Practice), North-West University, Potchefstroom Campus, 2015
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An analysis of antidepressant noncompliance in the private health sector of South Africa / Francois Naude SlabbertSlabbert, Francois Naude January 2014 (has links)
The main aim of the thesis was to measure antidepressant (AD) non-compliance, to determine which factors are closely associated with AD non-compliance and the consequences of prolonged AD non-compliance in the private health sector of South Africa. The empirical study followed an observational, prospective, cohort study using longitudinal medicine claims data provided by a nationally representative Pharmaceutical Benefit Management company (PBM) from 1 January 2006 to 31 December 2011.
Failure to respond to AD treatment and achieving remission has severe neurobiological and clinical consequences. The clinical consequences include increased social and functional impairment, higher risk for recurrence and relapse of a depressive episode, a weak treatment outcome, significant increase in treatment cost, over-utilization of health care systems, and ultimately an increased suicide risk. However, the neurobiological consequences are much more far reaching. One of the more serious yet under-recognized neurobiological complications of AD non-compliance is the development of antidepressant discontinuation syndrome (ADS), which is the result of non-compliance or the abrupt discontinuation of AD treatment. Altered serotonergic dysfunction appears central to ADS so that how an antidepressant targets serotonin will determine its relative risk for inducing ADS and thereby affect later treatment outcome. Low ADS risk with agomelatine versus other antidepressants can be ascribed to its unique pharmacokinetic characteristics as well as its distinctive actions on serotonin, including melatonergic, monoaminergic and glutamatergic-nitrergic systems.
After the first four months only 34% (n=12 397) of patients were compliant. What’s more a statistically significant association was found between active ingredient consumed and compliance (p < 0.0001). Only 26.2% of patients who received amitriptyline-containing products were complaint compared to 38.8% and 38.7% in the cases of venlafaxine and duloxetine, respectively. The current study found that females have a significantly higher prevalence of MDD and HIV/AIDS when compared to males.
The co-morbidity between HIV/AIDS and major depressive disorder (MDD) had a significant effect on AD treatment compliance as patients diagnosed with both HIV/AIDS and MDD (74.43. ± 32.03, 95%Cl: 71.51-77.34) displayed a lower compliance vs. MDD patients (80.94% ± 29.44, 95%Cl: 80.56-81.33). Noteworthy, observations were that 75% (p < 0.0217; Cramer’s V = 0.0388) of venlafaxine and 28.6% (p < 0.0197; Cramer’s V = -0.0705) of the paroxetine items were compliant in patients diagnosed with both HIV/AIDS and MDD.
The overall compliance (35.19% acceptable compliance; n = 42 869) of patients taking both ADs and GDs was weak. In the group receiving both AD and GDs, an increased AD treatment period was associated with a significant increase (p < 0.0001) in AD compliance (406.60 days; 95%Cl: 403.20 – 409.90 vs. 252.70 days; 95%Cl: 250.20 – 255.20). In this cohort amitriptyline (29.57%), mirtazapine (31.36%) and fluoxetine (32.29%) were associated with the lowest levels of compliance, while duloxetine (40.67%) was found to have the highest compliance. Lastly, ADs with highest non-compliance were associated with an increase use in GDs. Alprazolam (n = 10 201) and zolpidem (n = 9 312) were the most frequently dispensed GDs in combination with AD treatment.
In conclusion the current study confirms that AD non-compliance is as big an obstacle in developing countries as it is in developed countries. Antidepressant treatment non-compliance has far reaching
consequences especially with the development of ADS which further complicates MDD and might be a precursor for the development of TRD. Several factors were found to be closely associated with AD treatment non-compliance which include; pharmacological class of AD, gender, chronic co-morbid illnesses and a short treatment period. / PhD (Pharmacy Practice), North-West University, Potchefstroom Campus, 2015
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ANTOCIANINAS DE AMORA BRAZO: EXTRAÇÃO, ESTABILIDADE E COPIGMENTAÇávila, Suelen 13 February 2015 (has links)
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Previous issue date: 2015-02-13 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Anthocyanins are natural colorants that provide attractive and bright colors to most plants, coloring them the bright red to violet. Due to its instability facing the food processing steps and their difficulty of extraction are still little used in the food industry. Flavonoids not anthocyanins, amino acids, nucleosides, organic acids and anthocyanins themselves may act as copigments enabling the anthocyanins as natural colorants. The objective was to evaluate the approximate composition, phenolic compounds, antioxidant activity of blackberries Brazo (Morus nigra L.) and the stability of anthocyanins. The effect of the addition of organic acids and polyphenolic extract of Camellia sinensis raw extract of blackberries anthocyanins as copigments. The copigmentation reaction buffer at pH 3.0, was confirmed by UV-Visible absorption and by high high-performance liquid chromatography analysis. The calculated half-life and the color retention percentage. The response surface methodology was effective to estimate the effect of three independent variables on anthocyanins extraction, the optimal values suggested for the extraction with citric acid were time of 60 min., ratio of 1 g / 30 mL and a temperature of 60 ºC and the extraction with hydrochloric acid have been suggested the same conditions of time and ratio, but at 20 ° C. The increase in relation copigmento / anthocyanins was evidenced by the bathochromic and hyperchromic effects. The interaction of anthocyanins was significantly affected by temperature (5 ± 3 ° C and 25 ± 3 ° C) and the environment (light and dark). The stability of anthocyanins with added copigmento increased half-life and the color retention percentage of sample. Maximum stability was achieved in samples with the addition of caffeic acid at a temperature of 5 ° C ± 3 ° C in the dark. Anthocyanins added caffeic acid and malic showed half-life of 242.40 ± 25.40 and 200.48 ± 12.15 days, respectively, bringing prospects for application of this natural dye. / Antocianinas são corantes naturais que proporcionam cores atrativas e brilhantes à maioria das plantas, colorindo-as do vermelho vivo ao violeta. Devido à sua instabilidade frente às etapas de processamento de alimentos e a sua dificuldade de extração ainda são pouco utilizados na indústria alimentícia. Flavonóides não antociânicos, aminoácidos, nucleosídios, ácidos orgânicos e as próprias antocianinas podem agir como copigmentos viabilizando as antocianinas como corantes naturais. O objetivo do trabalho foi avaliar a composição aproximada, os compostos fenólicos totais, a atividade antioxidante de amoras Brazo (Morus nigra L.) e a estabilidade das suas antocianinas. Foi avaliado o efeito da adição dos ácidos orgânicos e extrato polifenólico de Camellia sinensis ao extrato bruto de antocianinas de amora como copigmentos. A reação de copigmentação em solução tampão pH 3,0, foi confirmada por espectrofotometria de absorção UV-Visível e por análise cromatográfica líquida de alta eficiência. Calculou-se o tempo de meia vida e a percentagem de retenção de cor. A metodologia de superfície de resposta foi eficaz para estimar o efeito de três variáveis independentes sobre a extração de antocianinas, os ótimos valores sugeridos para a extração com ácido cítrico foram tempo de 60 min., razão de 1g / 30 mL e uma temperatura de 60°C e para a extração com ácido clorídrico foram sugeridas as mesmas condições de tempo e razão, porém a uma temperatura de 20°C. O aumento na relação copigmento/antocianinas foi evidenciado pelos efeitos batocrômico e hipercrômico. A interação das antocianinas foi significativamente afetada pela temperatura (5±3ºC e 25±3ºC) e o ambiente (luz e escuro). A estabilidade das antocianinas com adição de copigmento aumentou o tempo de meia vida e a porcentagem de retenção de cor das amostras. A estabilidade máxima foi alcançada nas amostras com adição de ácido cafeico em temperatura de 5ºC±3°C e no escuro. As antocianinas adicionadas de ácido cafeico e málico apresentaram tempo de meia vida de 242,40 ± 25,40 e 200,48 ± 12,15 dias, respectivamente, trazendo perspectivas para aplicação deste corante natural.
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When engineering new recombinant factor IX molecules meets gene therapy : improvement of factor IX plasma level in patients with haemophilia B? / Quand la création de nouvelles molécules recombinantes de facteur IX de la coagulation rencontre la thérapie génique : pourrait-on davantage améliorer le niveau plasmatique de facteur IX chez les patients hémophiles B ?Le Quellec, Sandra 28 November 2018 (has links)
Introduction : L’hémophilie B (HB) est une maladie hémorragique héréditaire caractérisée par un déficit en facteur IX (FIX) de la coagulation. La thérapie génique de l’HB par injection de virus adéno-associés (AAV) montre des résultats prometteurs, mais entraine une toxicité hépatique à forte dose. La création de nouveau transgène de FIX permettant d’injecter de moindres doses d’AAV est un réel enjeu. Matériel et Méthodes : Des transgènes thérapeutiques exprimant une protéine humaine de FIX à demi-vie prolongée par fusion à l’albumine (hFIX-Alb) ou exprimant un FIX une activité spécifique augmentée, le hFIX-E410H, ont été créés et injectés à des modèles murins. Une nouvelle molécule recombinante de hFIX à demi-vie prolongée par fusion à la sous-unité B du FXIII via un linker clivable par le facteur X activé (hFIX-LXa-FXIIIB) a été crée, produite et caractérisée. Résultats : Le transgène hFIX-Alb n’accumulait pas le niveau plasmatique du FIX par rapport au FIX sauvage. Des expériences ont été entreprises pour comprendre les mécanismes responsables du défaut d’expression. Le transgène hFIX-E410H, montrant une activité spécifique augmentée in vitro et in vivo chez les souris HB, permettait de diminuer les doses d’AAV d’environ 2,5 fois. La molécule hFIX-LXa-FXIIIB était fonctionnelle, corrigeait la génération de thrombine chez les souris HB, et présentait une demi-vie augmentée 3,9 fois chez la souris et 2,3 fois chez le rat. Conclusion : Nous avons développé et caractérisé de nouveaux transgènes de FIX modifiés et une nouvelle molécule de FIX à demi-vie prolongée, qui pourraient constituer de nouvelles perspectives thérapeutiques de l’HB / Introduction: Haemophilia B (HB) is an inherited bleeding disorder due to coagulation factor IX (FIX) deficiency. Adeno-associated virus (AAV)-based gene therapy for HB has shown promising results but can cause liver toxicity after administration of high dose of AAV vectors.The design of new transgene expressing modified FIX that would allow injecting fewer doses of AAV is a real challenge. Materials & Methods: Therapeutic transgene expressing human FIX with prolonged half-life due to fusion to mature albumin (hFIX-Alb) or expressing FIX with improved specific activity, hFIX-E410H, were designed and injected to murine animal model. A novel recombinant FIX molecule exhibiting enhanced half-life through fusion to the FXIIIB subunit via activated factor X-cleavable linker was design, produced and characterised. Results: The hFIX-Alb transgene did not increase the plasma FIX clotting activity compared to the transgene expressing wild-type hFIX. Experiments were undertaken to understand the mecanisms responsible for lower expression. The hFIX-E410H transgene, which showed improved specific activity in vitro and in vivo in HB mice, allowed injecting a 2.5-fold lower dose of AAV. The hFIX-LXa-FXIIIB molecule was functional, corrected the generation capacity in HB mice, and exhibited a 3.9-fold and 2.2-fold enhanced half-life in mice and in rats, respectively, compared to wild-type FIX. Conclusion: We have developed and characterised new transgenes expressing modified FIX, and a novel FIX molecule with prolonged half-life, which could become interesting perspectives for the treatment of HB
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Decomposição e mineralização de adubos orgânicos acondicionados em cápsulas porosas / Decomposition and nutrient mineralization of organic fertilizers into porous capsulesPereira, Dercio Ceri 11 July 2011 (has links)
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Previous issue date: 2011-07-11 / The western Paraná is a region that rears poultry, swine and cattle. Such activities
produce significant amounts of waste. The increase on its amount is due to an animal
intensive system, whose management is in feedlot and adopts large herds per unit
area. The use of organic waste in agriculture is increasing due to some awareness of
organic manure application in the studied region. Thus, this study aimed at
investigating the decomposition of organic fertilizers produced in western Paraná as
well as nutrients mineralization and the effect of their contents on soil bellow porous
capsules, without and with irrigation. Porous capsules (ceramic candles) were used,
whose diameter was 5.1 cm and 9.8 cm length. The experimental design was in
randomized blocks with five treatments. Two trials were carried out: one with 100
capsules under irrigation and the second one without irrigation. The treatments were:
pelletized vermicompost (V); pelletized vermicompost + phosphate Arad (VP); compost
(C); biodynamic compost (BC); poultry litter of three batches (PL). In order to place the
capsules, furrows were opened deeper than the capsules diameter (5 cm) and covered
with a layer of soil. The capsules were put horizontally on soil profile. Irrigation was by
drip. Samples of such organic materials were collected for analyses at 7, 14, 35, 65
and 100 days. The material inside capsules was oven-dried and weighed to determine
decomposition by difference of mass. The contents of nitrogen, phosphorus,
potassium, calcium, magnesium, zinc, iron, copper and manganese of different organic
materials were evaluated with and without irrigation. For soil, the same nutrients of
organic materials were analyzed, except for nitrogen; besides, carbon contents were
determined. The decomposition rate was estimated by logarithmic equations, as well
as half-life of organic materials. The PL treatment without irrigation showed higher
decomposition of organic materials (V, VP, C, CB), as well as for the irrigation system.
On the other hand, the decomposition of organic materials (V, VP, C, CB) in the
irrigated area was superior than without irrigation. The PL mineralization for nutrients
as carbon, nitrogen, phosphorus, potassium, sodium, zinc, iron, copper and
manganese was higher in non-irrigated area when compared with the other treatments
and in relation to the area under irrigation. The organic materials (V, VP, C and CB) in
relation to nutrients as carbon, nitrogen, phosphorus, potassium, sodium, zinc, iron,
copper and manganese showed a better answer in mineralization when under an
irrigation system. / A Região Oeste do Paraná possui criações de aves, suínos e bovinos. Tais atividades
geram quantidades significativas de resíduos. O aumento no volume de dejetos é
devido à intensificação da produção de proteína animal, que faz uso de confinamento
e adota grandes plantéis de animais por unidade de área. A utilização dos resíduos
orgânicos na agricultura está aumentando, devido à conscientização acerca da
utilização da adubação orgânica na Região. Assim, o objetivo deste estudo foi verificar
a decomposição dos adubos orgânicos, gerados na Região Oeste do Paraná, bem
como a mineralização dos nutrientes e o efeito sobre os teores destes no solo abaixo
das cápsulas sem irrigação e com irrigação. Foram utilizadas cápsulas porosas, com
diâmetro de 5,3 cm e 9,8 cm de comprimento. O delineamento experimental foi em
blocos casualizados com cinco tratamentos. Foram realizados dois experimentos com
100 cápsulas irrigadas e 100 cápsulas sem irrigação. Os tratamentos foram:
vermicomposto peletizado (V); vermicomposto peletizado + fosfato de Arad (VF);
composto (C); composto biodinâmico (CB); cama de aviário de três lotes (CA). Para a
acomodação das cápsulas, foram abertos sulcos com profundidade superior ao
diâmetro das cápsulas, e cobertas com uma camada de solo. As cápsulas foram
dispostas no sentido horizontal em relação ao perfil do solo. A irrigação foi por
gotejamento, efetuada a cada dois dias. As coletas dos materiais orgânicos para as
análises foram aos 7, 14, 35, 65 e 100 dias. O material orgânico do interior da cápsula
foi seco em estufa e pesado para determinar a decomposição por diferença de massa.
Foram avaliados teores de nitrogênio, fósforo, potássio, cálcio, magnésio, zinco, ferro,
cobre e manganês dos materiais orgânicos, com e sem irrigação. Para o solo, foram
analisados os mesmos nutrientes dos materiais orgânicos, exceto nitrogênio, mas
foram determinados os teores de carbono. A taxa de decomposição anual foi estimada
por meio de equações logarítmicas, assim como a meia-vida dos materiais orgânicos.
A CA, sem irrigação, apresentou maior decomposição entre os materiais orgânicos V,
VF, C, CB e em relação ao sistema irrigado. Por outro lado, a decomposição dos
materiais orgânicos V, VF, C, CB, na área irrigada, foi superior em relação à área sem
irrigação. A mineralização da CA para os nutrientes carbono, nitrogênio, fósforo,
potássio, sódio, zinco, ferro, cobre e manganês foi maior na área sem irrigação, em
comparação aos demais tratamentos e em relação à área com irrigação. Os materiais
orgânicos V, VF, C e CB para os elementos: carbono, nitrogênio, fósforo, potássio,
sódio, zinco, ferro, cobre e manganês apresentaram superioridade na mineralização
com a utilização do sistema irrigado.
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Decomposição e mineralização de adubos orgânicos acondicionados em cápsulas porosas / Decomposition and nutrient mineralization of organic fertilizers into porous capsulesPereira, Dercio Ceri 11 July 2011 (has links)
Made available in DSpace on 2017-05-12T14:48:15Z (GMT). No. of bitstreams: 1
Dercio_texto completo.pdf: 1537971 bytes, checksum: 6f0c7593eb1fec03ef4d321153f4df61 (MD5)
Previous issue date: 2011-07-11 / The western Paraná is a region that rears poultry, swine and cattle. Such activities
produce significant amounts of waste. The increase on its amount is due to an animal
intensive system, whose management is in feedlot and adopts large herds per unit
area. The use of organic waste in agriculture is increasing due to some awareness of
organic manure application in the studied region. Thus, this study aimed at
investigating the decomposition of organic fertilizers produced in western Paraná as
well as nutrients mineralization and the effect of their contents on soil bellow porous
capsules, without and with irrigation. Porous capsules (ceramic candles) were used,
whose diameter was 5.1 cm and 9.8 cm length. The experimental design was in
randomized blocks with five treatments. Two trials were carried out: one with 100
capsules under irrigation and the second one without irrigation. The treatments were:
pelletized vermicompost (V); pelletized vermicompost + phosphate Arad (VP); compost
(C); biodynamic compost (BC); poultry litter of three batches (PL). In order to place the
capsules, furrows were opened deeper than the capsules diameter (5 cm) and covered
with a layer of soil. The capsules were put horizontally on soil profile. Irrigation was by
drip. Samples of such organic materials were collected for analyses at 7, 14, 35, 65
and 100 days. The material inside capsules was oven-dried and weighed to determine
decomposition by difference of mass. The contents of nitrogen, phosphorus,
potassium, calcium, magnesium, zinc, iron, copper and manganese of different organic
materials were evaluated with and without irrigation. For soil, the same nutrients of
organic materials were analyzed, except for nitrogen; besides, carbon contents were
determined. The decomposition rate was estimated by logarithmic equations, as well
as half-life of organic materials. The PL treatment without irrigation showed higher
decomposition of organic materials (V, VP, C, CB), as well as for the irrigation system.
On the other hand, the decomposition of organic materials (V, VP, C, CB) in the
irrigated area was superior than without irrigation. The PL mineralization for nutrients
as carbon, nitrogen, phosphorus, potassium, sodium, zinc, iron, copper and
manganese was higher in non-irrigated area when compared with the other treatments
and in relation to the area under irrigation. The organic materials (V, VP, C and CB) in
relation to nutrients as carbon, nitrogen, phosphorus, potassium, sodium, zinc, iron,
copper and manganese showed a better answer in mineralization when under an
irrigation system. / A Região Oeste do Paraná possui criações de aves, suínos e bovinos. Tais atividades
geram quantidades significativas de resíduos. O aumento no volume de dejetos é
devido à intensificação da produção de proteína animal, que faz uso de confinamento
e adota grandes plantéis de animais por unidade de área. A utilização dos resíduos
orgânicos na agricultura está aumentando, devido à conscientização acerca da
utilização da adubação orgânica na Região. Assim, o objetivo deste estudo foi verificar
a decomposição dos adubos orgânicos, gerados na Região Oeste do Paraná, bem
como a mineralização dos nutrientes e o efeito sobre os teores destes no solo abaixo
das cápsulas sem irrigação e com irrigação. Foram utilizadas cápsulas porosas, com
diâmetro de 5,3 cm e 9,8 cm de comprimento. O delineamento experimental foi em
blocos casualizados com cinco tratamentos. Foram realizados dois experimentos com
100 cápsulas irrigadas e 100 cápsulas sem irrigação. Os tratamentos foram:
vermicomposto peletizado (V); vermicomposto peletizado + fosfato de Arad (VF);
composto (C); composto biodinâmico (CB); cama de aviário de três lotes (CA). Para a
acomodação das cápsulas, foram abertos sulcos com profundidade superior ao
diâmetro das cápsulas, e cobertas com uma camada de solo. As cápsulas foram
dispostas no sentido horizontal em relação ao perfil do solo. A irrigação foi por
gotejamento, efetuada a cada dois dias. As coletas dos materiais orgânicos para as
análises foram aos 7, 14, 35, 65 e 100 dias. O material orgânico do interior da cápsula
foi seco em estufa e pesado para determinar a decomposição por diferença de massa.
Foram avaliados teores de nitrogênio, fósforo, potássio, cálcio, magnésio, zinco, ferro,
cobre e manganês dos materiais orgânicos, com e sem irrigação. Para o solo, foram
analisados os mesmos nutrientes dos materiais orgânicos, exceto nitrogênio, mas
foram determinados os teores de carbono. A taxa de decomposição anual foi estimada
por meio de equações logarítmicas, assim como a meia-vida dos materiais orgânicos.
A CA, sem irrigação, apresentou maior decomposição entre os materiais orgânicos V,
VF, C, CB e em relação ao sistema irrigado. Por outro lado, a decomposição dos
materiais orgânicos V, VF, C, CB, na área irrigada, foi superior em relação à área sem
irrigação. A mineralização da CA para os nutrientes carbono, nitrogênio, fósforo,
potássio, sódio, zinco, ferro, cobre e manganês foi maior na área sem irrigação, em
comparação aos demais tratamentos e em relação à área com irrigação. Os materiais
orgânicos V, VF, C e CB para os elementos: carbono, nitrogênio, fósforo, potássio,
sódio, zinco, ferro, cobre e manganês apresentaram superioridade na mineralização
com a utilização do sistema irrigado.
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Velocidade de decomposição da fitomassa do crambe em Latossolo argiloso sob sistemas de manejo / Rate of decomposition of crambe phytomass on oxisol under soil management practicesMartins, Marcos Felipe Leal 26 February 2016 (has links)
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Previous issue date: 2016-02-26 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The aim of this study is to evaluate the rate of decomposition of straw on crambe cover crop based on no-tillage system under different soil management practices and usages. We attempt to approach the practice adopted by farmers in the western region of Paraná. The experiment was conducted in the experimental area of the Agronomic Institute of Paraná - IAPAR, regional center of Santa Tereza do Oeste, Paraná, Brazil. The experiment consisted of four soil management practices: Traditional Tillage System - SPDT - Scarified Tillage System - SPDE - Gypsum Agricultural Tillage System - SPDG - and Tillage System with Quality - SPDQ. The treatments were distributed in randomized order on portions subdivided on time with fifteen macro-plots of 20 m x 25 m. The assessments took place on 0 (zero), 7, 15, 30, 60, 90, and 120 days after the harvest of crambe. Decomposition was determined quantitatively by the analysis of the rate of decomposition of crop residues using litterbags. The average loss of phytomass of crambe crop was significantly different (p>0,05), specially for SPDE and SDPG, which had reduction of around 0,63% day-1 and 0,71% day-1, respectively. The longest half-life period was observed on system SPDQ-12, with 66 days. The shortest half-life period was observed on system SPDE, with 45 days. / O objetivo do presente trabalho foi avaliar a velocidade de decomposição da palha em cobertura da espécie do crambe em diferentes usos e manejos do solo com base no sistema plantio direto. Buscou-se aproximar da prática adotada pelos produtores rurais da região oeste paranaense. O experimento foi conduzido na área experimental do Instituto Agronômico do Paraná - IAPAR, pólo regional de Santa Tereza do Oeste, Paraná, Brasil. Os tratamentos foram constituídos de quatro sistemas de manejo do solo, sendo estes: Sistema Plantio Direto Tradicional - SPDT -, Sistema Plantio Direto Escarificado - SPDE -, Sistema Plantio Direto Gessado - SPDG -, e Sistema Plantio Direto com Qualidade - SPDQ. Os tratamentos foram distribuídos de modo inteiramente casualizados em parcelas subdivididas no tempo com quinze macro-parcelas de 20 m x 25 m. As avaliações no tempo ocorreram aos 0 (zero), 7, 15, 30, 60, 90 e 120 dias após colheita do crambe. A determinação da decomposição seguiu-se de forma quantitativa, por meio da análise da taxa de decomposição dos resíduos culturais com o uso de litter bags . A perda média de fitomassa da cultura do crambe foi significativamente diferente (p>0,05) principalmente para o manejo SPDE e SDPG, a qual tiveram reduções respectivamente de 0,63 % dia-1 e 0,71 % dia-1. Para o tempo de meia vida o maior tempo constatado foi no sistema tratamento que continha como manejo o consórcio composto de Aveia preta cabocla + Tremoço branco, com 66 dias, já o menor tempo de meia vida foi observado para o sistema SPDE, com 45 dias. O sistema de manejo influenciou no tempo de meia-vida dos resíduos reduzindo em até 21 dias.
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Thorium–based fuel cycles : saving uranium in a 200 MWth pebble bed high temperature reactor / S.K. GintnerGintner, Stephan Konrad January 2010 (has links)
The predominant nuclear fuel used globally at present is uranium which is a finite resource. Thorium has been identified as an alternative nuclear fuel source that can be utilized in almost all existing uranium–based reactors and can significantly help in conserving limited uranium reserves. Furthermore, the elimination of proliferation risks associated with thorium–based fuel cycles is a key reason for re–evaluating the possible utilization of thorium in high temperature reactors. In addition to the many advantages that thorium–based fuel has over uranium–based fuel, there are vast thorium resources in the earth's crust that up until the present have not been exploited optimally.
This study focuses on determining the amount of uranium ore that can be saved using thorium as a nuclear fuel in HTR's. Four identical 200 MWth high temperature reactors are considered which make use of different fuel cycles. These fuel cycles range from the conventional uranium fuel cycle to a thorium–based fuel cycle in which no U–238 is present and have been simulated using the VSOP–A system of computer codes. This study also considers the effect that protactinium, an isotope that occurs in thorium–based fuel cycles, will have on the decay heat production in the case of a depressurized loss of coolant (DLOFC) accident. / Thesis (M.Ing. (Nuclear Engineering))--North-West University, Potchefstroom Campus, 2011.
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